Combination fltjid control and heating- device



March 24, 1925. 1,530,485

C. H. EASTMAN COMBINATION FLUID CONTROL AND HEATING DEVICE Filed Dec. 20, 1925 [7 ave 71/150 7".

from in the incorporation of a fuel heating Patented Mar. 24, 1925.

UNITED STATES PATENT OFFICE.

CHARLES -H. EASTMAN, 013 BOSTON, MASSACHUSETTS.

COMBINATION FLUID CONTROL AND HEATING DEVIGE.

Application filed December 20, 1923. se iainp. 681,749.

1 0. all whom it may concern:

Be it knownthatzl, CHARL-ns H. EASTYAN,

a citizen of the United States, residing at Boston, in the county of Suffolk and State of hilassachuse-tts, have invented new and device for heating fuel and operating inst-rumentalities requiring steady low pressures, which device when installed, requires no attention and cannot betampered with or altered by unauthorized persons.

The object of the invention is furtherto provide a device ofthe character set forth, which can be installed to operate at apredetermined pressure.

Another object of the device is to provide a device of the character set forth which is simple in its construction, ellicient in its operation and which has no changeable parts.

Another object of the invention is to provide a device of the character set forth which needs no more water added thereto after sufficient water for the waterseals has been introduced into the casing.

in certain respects the device of this invention is similar to the device of my in vention for which I have made application for United States Letters Patent filed February 2, 1922, Serial No. 538,727, now United States Letters Patent- No. l,505,38l patented August 1.9, 192%, but differs theredevice therein, whereby the fuel for the burner of a boiler is heated by the steam from that boiler and the control of the fuel to the burner is regulated according to the pressure of the steam. in the boiler. Another important improvement in the device of the present application, as compared with said Letters Patent, is the. means whereby the steam, which iscondensed in the device, is taken care of. Other details of construction enable the device to be positive and silent in its operation.

The device of this invention is adapted to be used in connection with fuel oil supply feeds, gas, air, steam, reducing valves, re-

lease valves, or any instrumentalities requ ring an unchangeable standard pressure. The device o-f-thisvmvention may be placed at any desired height from. the floor, or may be placed upon the floorif so desired, independent of the height of the water line of the boiler, or of low places in supply pipes, or Water accumulations from water, air, ga's,or steam, all these conditions being taken care of by a separator and by an overflow device connected to the separator and embodying a Water seal and operating to discharge into a sewer or any convenient place. i

The main supply to the combination control and heating device is taken from some.

source of pressure, and when the pressure has reached a predetermined amount the device of this invention is so adjusted or set, as to operate instrumentalities to preventthepressure fromfpassing beyond the predetermined amount.

p In the particular embodiment of my invention disclosed in the drawing of this application and hereinafter described in the specification, a fuel supply of oil is contemplated which is preheated in the device of this invention and the supply of fuel to the burner for a boiler is controlled by the device of this invention.

The device of this invention act-s directly upon the instnimentalit-ies which control the flow of the oil to the burner and the slightest drop in the pressure will operate to actuate such instrumentalit The action of the control device of this invention is positive, simple, very powerful, of'very few parts, and can be set to operate at any desired and predetermined pressure. I

To these ends and others hereinafter appearing in the specification, the invention consists in the combination and arrangement of parts set forth in the following specification and particularly pointed out in the claims thereof. p 1

Referring to the-dra .vings:

Figure 1 'a vertical sectional elevation of a fluidcontrol and fuel heating device embodying my invention.

Fig. 2 is a sectional plan 2-2 of'Figure 1.

Fig. 8 is a plan of the heater.

Fig, .4 is a. sectionalelevation of the heater.

taken on line Fig. 5 is a detail section taken on line A--A, Fig. 1.

Fig. 6 is a sectional elevation taken on line 66, Fig. 4.

Like numerals refer to like parts in the several views of the drawings.

In the drawings, 5 is a casing preferably cylindrical and closed at its opposite ends by a top 6 and a bottom 7. Inside the casing 5 a piston 8 is provided, which is open at the bottom and closed by a top 9. The top 9 has a valve 10 thereon adapted to contact with a seat 11 provided on the inner face of the top 6. A pipe 12, constituting a conduit, has permanent engagement with the top 9 and is provided with ports 13 and 14 and when the piston 8, is in its lowermost position, the port 13 is within the casing 5 and the port 14 is above the casing 5 and opens into the atmosphere. When the piston is in its uppermost position, the valve 10 confacts with the seat 11 and both of the ports 13 and 14 are above the top 6, whereby the interior of the casing 5 is closed to the atmosphere.

The upper end of the conduit 12 is closed by a plug 15 and has weights 16 thereon which rest upon a disc 17 which is fastened to the conduit.

The casing 5 is provided with a Water gauge 18, which registers the height of the water in the casing in a manner well known to those skilled in this art.

The piston 8 has positioned upon its lower end a plurality of anti-friction rolls 19 which contact with the interior of the casing 5 and constitute anti-friction guide mem bers for the lower end of the piston. The piston is further guided by anti-friction rolls 19 which are rotatably mounted upon the top 6 of the casing and contact with the vertical sliding conduit 12.

The bottom 7 of the casing has a conical upwardly extending standard 7 which pro jects into the piston 8 and terminates at the top in a closed upper end and at the bottom in an opening 21. A pipe 20 extends upwardly through an air chamber 21 in the standard 7 and terminates at a substantial distance above the upper end of the standard. The upper end of said pipe is open and it is provided with ports 22 just above the upper end of the standard 7, whereby the height of the water seal 23 is regulated as at AA.

The combined area of the ports 22 is ap proximately one-tenth of the area of the tube 20, so that if a vacuum should tend to form in the piston 8, water from the water seal 23 cannot be thrown in a large amount down the tube 20 into a chamber 25 in a separator 24 and interfere with the operation of a check valve 34, which opens from the atmosphere into said chamber.

The lower end of the pipe 20 is fastened therein, through which the pipe 20 passes,

being open at all times to the atmosphere,

eliminates any danger of heating the water in the water seal by the steam passing through the pipe 20.

The separator 24 has an auxiliary casing 27 fast to the bottom thereof and extending downwardly, terminating at its lower end in a flange 28 which is fastened to a base 29 which rests upon the floor or other convenient means of support. A pipe 30 is fastened at its upper end to a partition 31 at the bottom of the chamber 25 andv this pipe terminates at the bottom end there-- of, adjacent the bottom of the auxiliary casing 27. An outlet 32 is provided in the auxiliary casing 27, below the partition 31 and above the lower end of the pipe 30, and this outlet may be connected by pipes 33 to a sewer, or any other suitable receptacle for the overflow of water from the auxiliary casing 27.

The lengths of the pipe 30 and casing 27 vary according to the amount of fluid or steam pressure to be carried. A vent 33 is provided to prevent the liquid in the auxiliary casing 27 from being siphoned out, and a pet cock 27 serves to empty the auxiliary casing 27 when desired.

The check valve 34 is attached to the separator 24 and opens into the chamber 25, so that if any vacuum should form in the piston, air will enter through the check valve and break the vacuum.

A fuel heater 35 is provided inside the hollow piston 8 adjacent the upper end thereof and preferably consists of a hollow ring-shaped member provided with a chamber 36. A pipe 37 is connected to the bottom of the heater 35 and passes downwardly therefrom through the bottom 7 of the cas ing 5 and thence to a pump, not shown in the drawing, which forces oil through the pipe 37 into the chamber 36 and circulating through the chamber 36 the oil passes out of the heater 35 through an outlet pipe 38 which terminates at its upper end adjacent the upper end of the heater 35 and passes downwardly through the chamber 36, through the piston 8 and through the bottom 7 of the casing, thence extending downwardly and horizontally to connect with a burner 39 which is placed beneath the boiler, to which it is to supply heat.

An air outlet pipe 40, to conduct air out of the piston 8, passes upwardly through the bottom 7 and terminates at its upper end in a boss 41 which projects downwardly from the bottom of the heater 35. The upper end of the pipe is closed except for an air pipe 42 which, extends from the upper end of the pipe 40 through the boss 41, terminating at its upper end above the water seal line AA. The lower end, of the pipe 40 has a thermostatic valve 43 fast thereto, so that, as the steam enters the piston. 8, through the pipe 20, the air which is enclose d in the piston 8 will be forced out through the pipe 41, pipe 40 and thermostatic valve 43 until all the air is forced out and steam enters the pipe 40 and valve 43, whereupon said thermostatic valve will close.

A pressure regulating valve 44 is provided in some convenient place in the fuel supply pipe 38 and a regulating valve 45 is also provided in said pipe, which has a shut-off lever 46 connected thereto, the shut-off lever being operated by a rod 47 which is connected to a horizontal arm 48, supported upon one arm 49 of a double yoke 50 and projects at its inner end into a recess in a collar 51, which is in turn fastened to the conduit 12. Another arm 52 is supported on an arm 53 of the yoke 50 and terminates at its inner end in a recess in the collar 51, this arm being provided with a counterweight 54 to counterbalance the weight and pull upon the arm 48. The double yoke 50 is fastened to the conduit 12 by a set screw 56 and the collar 51 is fastened to the conduit by a set screw 57.

The general operation of the invention hereinbefo-re specifically described is as followsp-ulssuming liquid, such as water, to have been inserted through the opening which isclosed by a plug 55 in the top 6 to the height of the line AA, Fig.1, and that fluid, such as steam under pressure is introduced into the interior of the piston 8' through the pipe 26, separator 24 and pipe 20; all condensation of supply fluid is separated and flows from the separator 24 down wardly through the pipe 30 into the auxiliary casing27. Assuming the normal level of the water in the auxiliary casing and in the pipe 30 to be at the height of the line BB, the water 23 in the piston would be forced downwardly by the pressureof said steam and will be forced upwardly in the space between the piston 8 and the casing5. The air, which at that time is enclosed in the space between the piston and the casing, will pass through the holes 13, which are at that time positioned inside the casing 5 below the top 6 thereof, and will pass through the conduit 12 and outwardly to the atmosphere through the holes 14, which at that time are positioned above the top 6, as illustrated in Figure 1, while the air which is in the piston will pass through the pipe 41, pipe 40 and thermostatic valve 43 to the atmosphere.

This operation will continue, the piston rising, and the water between the walls of the piston and the casing also rising, and

the water inside the piston descending until the valve 10 contacts with the seat 11, as shown in dotted lines, Figure 1, at'which time the holes 13 will be located above the top 6.

the seat 11, the casing will be absolutely tight and no water, air, or steam can pass out of the casing, the valve lO when in the position illustrated in dotted lines, Figure 1, absolutely closing the casing against the passage of anything out of the same, and when the air in the piston has all passed out through the pipe 40 and valve 43 the heat of the steam will close the valve 43.

The vertical movement thus imparted to the piston will be transmitted by the conduit 12 to the rod 48, whereby any desired instrumentalities may be operated, but in the present embodiment of my invention, as illustrated in Fig. 1, the rod 48, when the conduit 12is moved upwardly, pulls upwardly on the rod 47 and rocks thelever 46 to partlyv close the valve 45 and thus decrease the amount of fuel supplied to the burner 39 through the pipe 38.

It will be understood that the number of weights 16 depends upon the pressure under which it is desired that the device of this invention shall operate.

It will be noted that the inner diameter of the separator is considerably larger than the inner diameter of the pipes 20 and 26 and as the vapor or steam fills the separator and moves very slowly through the pipes'20 and 26 to the interior of the piston- 8, liquid which condenses from said steam will fall to the bottom of the separator 24 lVhen the valve 10 contacts with in the chamber 25 and will pass downwardly through the pipe 30 and into the auxiliary casing 27 until it arrives at approximately the height indicated by the line BB.

The steam under pressure in the chamber 25 of the separator will force the condensed I water in the pipe 30 downwardly and will force the water in the auxiliary casing upwardly until it overflows through the pipe 33. At the same time the piston 8 will rise to the top of the cylinder. When the pressure of the fluid, steam, or whatever it may be, increases to the predetermined amount for which the piston is set, said piston will slowly rise until the valve portion 10 thereof contacts with the seat 11 and will remain in that position until the pressure in the separator drops below the amount which has been predetermined for the particular device under consideration, whereupon the piston will slowly return to its starting position and the level of the liquid in the piston and in the space between the piston and the casing will be at the line AA and the level of the liquid in the auxiliary casing will be at the line BB.

It will thus be seen that the surplus water of condensation is positively discharged out of the auxiliary casing 27 through the outlet 32 and through the pipes 33 without employing any valve, but depending entirely upon the pressure of the steam in the chamber 25 and upon the fixed pipes 30 and auxiliary casing 27.

Any of the steam which condenses 1n the piston above the line AA will flow out of the piston through the ports downwardly through the pipe and into the chamber and thence through the pipes into the auxiliary casing 27.

If vacuum, or partial vacuum should occur in the piston, it would be immediately overcome by air passing inwardly through the check valve 34 into the separator chamber and upwardly through the pipe 20 into the space in the piston above the water soul.

It will be seen that the standard 7 being open to the circulating atmosphere surrounding the pipe 20, the water seal 1n cylinder 5 and piston 8 is not heated by pipe 20. The steam which enters the piston will heat the fuel in the chamber 36 of the heater 35 and said fuel, passing into the chamber 36 through the pipe 37 and being forced through the said pipe by a pump, will circulate through and around the interior of the chamber 36 and will pass outwardly from said chamber through the pipe 38 to the burner 39, where it will burn and supply heat to a boiler, not shown in the drawing, whereby steam is provided in said boiler, and will pass from said boiler through the pipes 26 connected thereto, into the cham- .ber 25 of the separator 24, upwardly through the pipe 20 and into the piston 8 operating to partly shut off the fuel supply to the burner in the manner hereinbefore described.

The pressure to the burner is automatically regulated by a regulating valve 4a, and does away with objectionable feature of present usage, as pressures at burners largely vary, due to pump continuing to run when the burner is partly turned off.

The oil heater 36 consists of a hollow ringshaped structure, as shown in Figs. 1 and 1, both walls of which are entirely surrounded by steam and the oil therein being present in a thin sheet is very quickly heated, cold oil being delivered by pump through pipe 37 at bottom, heating and circulating to the top, thus passing through the pipe 38 to the regulating valve 415. The heater is a stationary fixture, supported on the bottom 7 by pipes 37, 38 and 40 and in no way interferes with the piston 8 performing its functions.

In the foregoing specification, the device of this invention is described and illustrated in the drawing as operating a single regulating valve 45, but if desired, a pair of regulating valves for burners under two separate boilers may be operated by substituting for the arm 52 another arm like the arm 48 and another rod like the rod 47, which will be connected to another shut-off lever and regulating valve like the shut-off lever 46 and regulating valve 45, so that the device of this invention may be utilized to operate more than one fuel regulating instrumentality or other instrumentalities at the same time.

It will be seen that the travel of the piston 8 may be regulated by adjusting the yoke 50 and collar 51 longitudinally of the conduit 12, for example, in Figure 1, if it is desired to shorten the travel of the piston S upwardly the set screws 56 and 57 may be loosened and the conduit 12, together with the piston 8 moved upwardly and then the set screws tightened again, so that the piston will have less travel before the valve 10 contacts with its seat 11.

It will also be noted that the piston 8, conduit 12, yoke 50, collar 51, weights 16, arms 48 and 52 and counterweight oat, form a unit which can be rotated to any desired position by first disconnecting the rod 47 from the arm 18. This feature of the device is very convenient when it is desired to set up the device in a certain position.

I claim 1. A fluid control and heating device having, in combination, a boiler, a burner therefor, a fluid control device, a stationary fuel heater positioned in said fluid control device, means to convey fuel to said heater and from said heater to said burner and means to convey steam from said boiler into said fluid control device, whereby said fuel may be heated and said fluid control device may be operated to control the flow of fuel to said burner.

2. A fluid control and heating device having, in combination, a boiler, a burner therefor, a fluid control device including a casing for controlling the supply of fuel to said burner, a stationary fuel heater in said casing, means to convey fuel to said heater and from said heater to said burner and means to convey steam from said boiler into said casing, whereby said fuel may be heated and said fluid control device may be operated to control the flow of fuel to said burner.

3. An automatic fluid control device having, in combination, a burner, a hollow casing, a hollow piston in said casing closed at its upper end and open at its lower end, said casing being adapted to contain liquid forming a liquid seal between said casing and piston, a stationary fuel heater located inside said piston, a pipe leading into said heater and a pipe leading out of said heater to said burner, means to convey heated fluid to the interior of said piston above the liquid therein and a member outside said casing 7 into said heater, and a pipe closed at its upper said hollow standard into the "interior said casing from ait P t l and connected to said piston, whereby instrumentalities outside said casing may be operated to control the flow, of fuel from said heaterto said bru'ner. l 4. An automatic fluid cpntrol device hav} lng, in combination, a hollow casing, a hollow piston in said casing, closed at its upper end and open at its lower end, said casing beingadapted to contain'liquid forming a liquid seal between. said casing and'piston,a hollow standard. projecting from" the -lewer end of said casingupwardly therein, closed at its upper end and'open at its lower'end and means extending upwardly through said standard to convey fluid to the interior of said piston above the liquid therein and a member outside said casing and conneeted to said piston, whereby instrumentalities outside said casing maybe operated.

5. An automatic fluid control device having, in combination, a hollow, "casing, a'hollow piston in said casing closed itsupper end and open at its lower end, said casing being adapted tocontain liquidforn iii a liquid seal betweensaid casing a' nd p s on, a hollow standard extending upwardly to said casing from the lower 'end thereof, end and open at its lower end, a pipe leading upwardly througu 0 said piston. and open atits'upper'end. and

a member outsidesaid casing and connected to, said piston, whereby instruinentalities Outs de d e' ings b new 6- An. wanna flu d a bntr l device ha ing, in combination, ahollo wjc i low pistonin said casingclqsedatits upper end and open at its lower end, "said; casing bei a ap sd n i ui rm ne' liquid seal between casing: pison, a hollow standard extending 'n-p lardly. into Y t llvei' e dt i le at approximately the normal level of'tlie liquid in said liquid seal, a pipe extending upwardly through said. standard in 'o theinterior of said piston and openat vits'upper end, said pipe being provided with a port spaced apart vfrom its upper lend and-fpositi ned Dirt-la ab e he pr e of a d he l wst n ir and a member outside said casing conneste t0: u p t n, wher by instrumentalities outside said easing may be operated. "7'. .An automatic fluidicontrolfdevice havng, in co nbinati on, a burner, a hollow c as-.

ving closed at its lower end, a hollow piston in said casing closed at its upper end and open at its lower end, gardening being adapted to contain liquid form'i a liquid s n b w sa rang a d pi t n, been;

a burner therefor, a stationary fuel heater located inside said piston, a pipe leading leading out .of id burner, a. hollow standard said heater to extending upwardly from the lower-end of said res ns; s eesds i J P -Z I I outside said casing and connected to said piston, whereby instrumentalities outside said casing may be operated to control the "How of fuel from said heater to said burner.

8. An automatic fluid control device having, in combination, a hollow casing closed at its lower end, a hollow piston in said casing, closed at its upper end and open at its lower end, said casing being adapted to contain liquid forming a liquid seal between said casing and piston, a pipe extending through the bottom of said casing and into the interior of said piston, a separator fast to said pipe and extending downwardly therefrom, said separator being closed at its lower end, an auxiliary casing fast to said separator and extending downwardly therefrom, a pipe leading from said separator into said auxiliary casing, said auxiliary casing being provided with .an outlet above the lower end of the pipe therein, liquid in said auxiliary casing forming a liquid seal and a pipe leading into said separator and adapted to be connected to a source of fluid under pressure. i v 9. An automatic fluid control device having, in combination, a hollow casing closed at its lower end, hollow piston in said casing closed at its upper end and open at its lower end, said'casing being adapted to contain liquid forming a liquid seal between said casing and piston, a pipe extending through the bottom of said casing and into the interior of 'said piston, a separator fast to said pipe and extending downwardly therefrom, said separator being closed at its lower end, an auxiliary casing fast to said separator and extending downwardly therefrom, a pipe leading from said separator into said auxiliary casing, said auxiliary casing being provided with an outlet above the lower end of'the pipe therein, liquid in said auxiliary casing forming a liquid seal, a pipe leading into said separator and adapted-to be connected to a source of fluid under 1 pressure and a check valve opening into said separator.

' 10. 'An automatic fluid control device having, in combination, a hollow casing closed at its lower end, a hollow piston in said casing closed at its upper end and open at its lower end, said casing being adapted to contain liquid'forming a liquid seal between said casing and piston, a pipe extending throughthe bottom of said casing and into the interior of said piston, a separator, fast to said pipe and extending downwardly therefrom, said separator being closed at therefrom, a pipe leading from said separator into said auxiliary casing, said auxiliary casing being provided with an outlet above the lower end of the pipe therein, liquid in said auxiliary casing forming a liquid seal, a pipe leading into said separator and adapted to be connected to a source of fluid under pressure, a check valve opening into said separator and a base fast to the lower end of said auxiliary casing.

11. An automatic fluid control device having, in combination, a burner, a hollow casing, closed at its lower end, a hollow piston in said casing closed at its upper end and open at its lower end, said casing being adapted to contain liquid forming a liquid seal between said casing and piston, a stationary fuel heater located inside said piston, a pipe leading into said heater and a pipe leading out of said heater to said burner, means to convey heated fluid to the interior of said piston above the liquid therein, a member outside said casing and connected to said piston whereby instrumentalities outside said casing may be operated to control the flow of fuel from said heater to said burner and means operated by said piston to open and close communication be tween the interior of said casing and the atmosphere.

'12. An automatic fluid control device having, in combination, a burner, a hollow casing closed at its lower end, a hollow piston in said casing closed at its upper end and open at its lower end, said casing being adapted to contain liquid forming a liquid seal between said casing and piston, a stationary fuel heater located inside said piston, a pipe leading into said heater and a pipe leading out of said heater to said burner, means to convey heated fluid to the interior of said piston above the liquid therein, a member outside said casing and connected to said piston, whereby instrumentalities outside said casing may be operated and a valve operated by said piston to open and close communication between the interior of said casing and the atmosphere.

13. An automatic fluid control device having, in combination, a burner, a hollow casing closed at its lower end, a hollow piston insaid casing closed at its upper end and open at its lower end, said casing being adapted to contain liquid forming a liqui seal between said casing and piston, a stationary fuel heater located inside said piston, a pipe leading into said heater and a pipe leading out of said heater to said burner, means to convey heated fluid to the interior of said piston above the liquid therein and a conduit fast to the outer end of said piston and projecting through the top of said casing, whereby instrumentalities outside said casing may be operated to control the flow of fluid from said heater to said burner.

14. An automatic fluid control device having, in combination, a hollow casing, a hollow piston slidable in said" casing, closed at its upper end and open at its lower end, said casing being adapted to contain liquid forming a liquid seal between said casing and piston, means to convey heated fluid under pressure to the interior of said piston, a member fast to the upper end of said piston, whereby instrumentalities outside said casing may be operated, and a pipe leading from the interior of said piston above said liquid seal to the exterior of said casing, whereby air in said piston may be ejected therefrom by said fluid under pressure, and a thermostatic valve in said pipe adapted to be closed by the heat of said heated fluid after said air has been ejected.

15. An automatic fluid control device hav ing, in combination, a hollow casing, a hollow piston slidable in said casing closed at its upper end and open at its lower end, said casing being adapted to contain liquid forming a liquid seal between said casing and piston, means to convey heated fluid under pressure to the interior of said iston, a pipe leading from the interior of said piston above said water seal to the atmosphere and a thermostatic valve in said pipe, whereby air contained in said piston above said water seal may be forced through said pipe into the atmosphere by said heated fluid under pressure, and said thermostatic valve subsequently closed.

16. An automatic fluid control device having, in combination, a separator provided with a chamber, means for supplying fluid under pressure to said chamber, a hollow casing, a hollow piston in said casing closed at its upper end and open at its lower end, said casing being adapted to contain liquid forming a liquid seal between said casing and piston, means to convey fluid under pressure to the interior of said piston from said separator chamber, an auxiliary casing, a pipe leading from said separator chamber into said auxiliary casing, said auxiliary casing being provided with an outlet above the lower end of the pipe therein and said auxiliary casing being adapted to contain liquid forming a liquid seal between said outlet and the lower end of said pipe.

17. An automatic fuel control device having, in combination, a hollow casing closed at its lower end, a hollow piston in said casing closed at its upper end and open at its lower end, said casing being adapted to contain liquid forming a liquid seal between the casing and piston, a pipe extending through the bottom of said casing and upwardly into the interior of said piston, a supply pipe leading to a source of fluid under pressure, a separator interposedbetween said supply pipe and said first-named pipe and means connected to said separator to automatically allow liquid to pass out of the separator while preventing air from entering the same.

18. An automatic fuel control device having, in combination, a hollow casing closed at its lower end, a hollow piston in said casing closed at its upper end and open at its lower end, said casing being adapted to contain liquid forming a liquid seal between the casing and piston, a pipe extending through the bottom of said casing and upwardly into the interior of said piston, a supply pipe leading to a source of fluid under pressure, a separator interposed between said supply pipe and said first-named pipe, and means connected to said separator to allow air to enter the separator and pass thence into the I hollow piston in the event of a partial vacuum forming in said piston.

19. An automatlc fuel control device having, in combination, a hollow casing closed at its lower end, a hollow piston in said casing closed at its upper end and open at its lower end, said casing being adapted to contain liquid forming a liquid seal between the casing and piston, a pipe extending through the bottom of said casing and upwardly into the interior of said piston, a supply pipe leading to a source of fluid under pressure, a. separator interposed between said supply pipe and said first-named pipe, and means connected to said separator beneath said second-named pipe to allow liquid to pass out of said separator while preventing air from entering the same.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

CHARLES H. EASTMAN.

'Witnesses:

FRANKLIN E. Low, KATHRYN M. J OYGE. 

